1. Field of the Invention
The present invention relates to relaying requests and responses by using a plurality of data relaying devices that have shared data.
2. Description of the Related Art
Multi-processor configurations have been used to quickly process ever-increasing data in computing devices (for example, servers, workstations, personal computers, etc.) used in various systems.
A typical multi-processor configuration usually includes a data relaying device (for example, a crossbar switch, etc.) to improve the speed of data transfer among a plurality of central processing units (CPUs), main memories, and I/O devices.
Even though such data relaying devices improve the performance of the computing devices, if the system encounters some problem due to which the various processes performed by it are suspended, the enterprise offering various services using the system will incur heavy losses. Various remedial measures have been proposed for restoring the system in the event of a system-down situation and improving the reliability of such systems.
For example, a technology proposes providing two crossbar switches, the second one being a backup crossbar switch that can be used when the first one fails.
Further, in the technology disclosed in Japanese Patent Application Laid-open No. H10-143465, extra input/output ports are provided in the crossbar switch. If any input/output port fails, other input/output port is used.
In the technology proposing two crossbar switches, however, the system needs to be shut down to replace the failed crossbar switch.
In the technology proposed in Japanese Patent Application Laid-open No. H10-143465, again, if the crossbar switch itself breaks down, the system needs to be shut down to replace the failed crossbar switch.